Double-drive tandem roller



June 17, 1958 D. FLETCHER DOUBLE-DRIVE TANDEM ROLLER 5 Sheets-Sheet 1 Filed June 20, 1955 Dean FZeZ'c her INVENTOR 4 ATTORNEYS June 17, 1958 5 Sheets-Sheet 2 Filed June 20, 1955 Dean FZei'Cber INVENTOR ATTORNEYS June 17, 1958 D. FLETCHER 2,839,147

DOUBLE-DRIVE TANDEM ROLLER Filed June 20, 1955 5 Sheets-Sheet 3 Dean, Flei'c her INVENTOR I 1 I 1 V I 4 ATTORNEYS June 17, 1958 D. FLETCHER DOUBLE-DRIVE TANDEM ROLLER 5 Sheets-Sheet 4 Filed June 20, 1955 Mm mx Dean. 7Z6 i'c/zer ATTORNEYS.

June 17, 1958 D. FLETCHER DOUBLE-DRIVE TANDEM ROLLER 5 Sheets-Sheet 5 Filed June 20, 1955 Dean F Lei'c/zer' Mil WW INVENTOR ATTORNEYS.

United States Patent DOUBLE-DRIVE TANDEM ROLLER Dean Fletcher, Spring Valley, Calif.

Application June 20, 1955, Serial No. 516,445

2 Claims. (Cl. 180-50) This invention relates to a front and rear driven tandem roller.

An object of this invention is to provide an improved roller for use in smoothing the ground, which is provided with a pair of front and rear rollers with a driving means for the rollers and with means whereby the front rollers may rock about a longitudinal axis when moving over uneven ground.

A further object of this invention is to provide a doubledrive roller with hydroulic means for steering the front and rear rollers.

With the foregoing and other objects in view which will appear as the description proceeds, the invention consists of certain novel details of construction and combinations of parts, hereinafter more fully described and pointed out in the claims, it being understood that changes may be made in the construction and arrangement of parts without departing from the spirit of the invention as claimed.

Referring to the drawings:

Figure 1 is a detail side elevation of a double-drive tandem roller constructed according to an embodiment of this invention.

Fig. 2 is a detail side elevation opposite from Fig. 1 of the device.

Fig. 3 is a plan view of the device.

Fig. 4 is a fragmentary longitudinal section of the forward end of the device.

Fig. 5 is a detail front elevation of the device.

Fig. 6 is a sectional view taken on line 6-6 of Fig. 1.

Referring to the drawings the numeral 10 designates generally a frame structure embodying a pair of longitudinal channel frame members 11 which are fixed at their forward ends to a vertical plate 12. The frame members 11 are also connected together between the rear ends thereof by means of an upwardly extending arcnate plate 13 which forms a well or guard about a pair of rear wheels, as will be hereinafter described. The frame structure also includes an upper rear platform or support 14 which is fixed to the plate 13 and a cross bar 15 is secured to the plate or upper frame member 14.

A pair of rear rollers or wheels 16 are rotatably mounted on an axle 22 which is fixed between the lower arms 17 of a steering fork generally indicated at 18. The fork 18 includes a horizontal connecting bar or bight 19 extending between the arms 17 and an upwardly projecting spindle or stud 20 is carried by the bight 19 and is rotatable in a bearing 21 carried by the transverse bar or plate 15. The two rollers 16 are independent of each other on the shaft 22 and each roller on the outer side thereof has fixed thereto a sprocket 23. A differential 24 of conventional construction is fixed in the upper portion of the fork 18 and the differential includes a shaft 25 projecting from each end thereof having a small sprocket 26 fixed thereto about which a chain 27 engages. The chain 27 also engages about the large sprocket 23. The wheels 16 are of hollow construction "ice and each roller on the outer end thereof has removable plug 28 by means of which water may be deposited into the roller for providing the necessary weight.

The front end of the machine includes an upstanding plate 29 fixed between the frame bars 11. This plate 29 is braced by means of a pair of triangular bracing webs 30 fixed to the plate 29 and to the frame members 11. A front frame structure generally indicated at 31 is pivotally mounted on the plate 29 and the front frame structure includes a vertical rear plate 32 which is pivotally mounted on a pivot member 33 extending through the rear plate 32 and the stationary frame plate 29. A pair of forwardly extending channel bars 34 extend from the upper portion of plate 32, and the channel bars 34 are connected together between the ends thereof by means of a connecting member 35 having a spindle bearing 36 in the center thereof. The stationary frame plate 29 has fixed to the lower end thereof an arcuate flange 37 on which a plurality of rollers 38 are carried by means of radially disposed studs 39. The rollers 38 are adapted to bear against the forward side of plate 32 so as to hold this plate 32 in contact with the forward side of stationary plate 29.

The front frame structure 31 has disposed therein a front steering fork generally indicated at 40 and the steering fork 40 includes depending arms 41 having a shaft or axle 42 fixed therebetween. A pair of front rollers 43 are rotatably mounted on the axle or shaft 42 and are of hollow construction so that water may be placed within each roller in order to provide the desired weight. The upper end of the fork 40 has a spindle or stud shaft 44 extending into the bearing 36. A front differential 45 is fixed relatively to the upper portion of the fork 40 and includes outwardly projecting shafts 46 having fixed thereon sprockets 47; A chain 48 engages about each sprocket 47 and also engages about a large sprocket 49 fixed on the end of each front roller 43. The front and rear steering forks are rotated by hydraulic means and the hydraulic means includes front and rear hydraulic cylinders 50 and 51, respectively, which are pivotally secured at their inner ends by universal pivot means 52 and 53, respectively. The cylinder 50 and 51 are of like construction and each includes a plunger 54 which is pivotally connected as at 55, by a universal pivot connection such as a ball and socket connection, to an adjacent steering fork.

Fluid pressure is admitted to the hydraulic cylinders by means of fluid pressure lines 56 and 57 connected to a fluid controlling valve assembly 58 having a pair of regulating levers 59 and 60. Fluid is communicated with the valve structure 58 from a pump 61 carried by the frame 19. The fluid line 56 is connected with the rear portion of a hydraulic cylinder, wherein fluid line 57 is connected with the forward end of the hydraulic cylinder. An engine 62 is carried by the frame 10 adjacent the forward portion thereof and includes a drive shaft 63 having a pulley 64 fixed thereon. A belt 65 engages about pulley 64 and about a pulley 66 mounted on the pump shaft 67. The front and rear differentials 45 and 24 have extending inwardly therefrom drive shafts 68 and 69 which are connected with a gear box 70 supported by supporting means 71 from plate 29. Shaft 69 extends through an arcuate opening 69a formed in wall 32 and the forward end of the shaft 69 is splined in sleeve 6% (Fig. 4). The arcuate opening 69a permits plate 32 to pivot about pivot bolt 33 which is the axis of flange 37. A speed changer 72 is connected with the engine 62 by means of a flexible drive 73. A brake drum 74 is fixed to a driven shaft 75 extending from the speed changer 72 and a brake band 76 engages about the brake drum 74. The brake band 76 is constantly urged to release position by means of a spring 77 and brake band 76 is moved to a braking position by means of a lever 78 which is connected to a pedal 79 by means of a link 84 The engine 62 also has a speed changer 31 connected with the drive shaft 63 which is regulated by means of a pedal 82 connected with the control arm 83 of the speed changer 81' by means of a link 84. The rollers 16 and 43 are adapted to be sprinkled with water from a sprinkler head or manifold 85 disposed above the rollers and connected by means of a pipe 86 with a water tank 87. Each roller is maintained in a relatively clean condition by means of a pair of spring-pressed scrapers 88 and 89 pivotally carried by scraper supporting bars 90 which are fixed relatively to the forks 18 and 44). The scrapers 88 and 89 are constantly urged into engagement with the peripheral surfaces of the rollers by means of springs 91 and 92.

In use and operation of this machine the device is moved forward or backwards byoperation of the engine 62 and adjustment of the speed changer or gear strucmm 81. The steering forks 18 and 40 are turned by adjustment of the valve controlling levers 59 and 6G. The front and rear drive shaft 68 and 69 which have interposedtherein a pair of universal joints 168 and 168a, and 169 and 169a, are then rotated so as to rotate the front and rear rollers 43 and 16 relatively, in the desired direction. 7

Asthe machine moves over uneven ground the frame structure may have the front and rear portions thereof rock one relative to the other about the horizontal axis of pivot member 33. Each roller has disposed adjacent the outer end thereof a guard plate 93 so that the operator of the machine will be protected from the chain and sprocket driving means for the rollers which are disposed at the outer ends thereof.

What is claimed is:

l. A double-drive roller comprising a body frame, an

upwardly ofiset rear portion carried by said body frame, a rear steerable fork carried by said rearportion, a pair of rear rollers rotatably carried bysaid fork, a vertical plate fixedly carried by the front of said rear portion of said body frame, a front frame, said front frame including a rear plate confronting said vertical plate, said plates being pivotally mounted relative'to-each other about a longitudinally extending axis, said pivot mounting comprising a horizontal pivot extending through said vertical and rear plates longitudinally of said body and front frames, a transversely disposed upwardly concaved arcuate flange carried by said vertical plate and extending forwardly 4 therefrom beneath said rear plate of said front frame, rollers carried by said flange bearing against the front face of said rear plate to thereby hold said rear plate against the forward side of said vertical plate, a front steerable fork carried by said front frame, a pair of front rollers carried by said front steerable fork, a motor carried by said rear portion, means connecting said motor to said front and rear rollers, said means including a front drive shaft and a rear drive shaft, said front drive shaft extending rotatably through said vertical plate, said rear plate including an arcuate opening, said drive shaft extending through said arcuate opening to permit pivotal movement of said front and rear plates relative to each other without lateral movement of said drive shaft, and means for turning said front and rear forks.

2. A connection for a double-drive roller having a front body frame with a rear plate, a rear body frame with a front plate confronting said rear plate and pivotally connected thereto about a longitudinally extending axis, and an axle operatively associated with said rear plate; said connection comprising an arcuate upwardly concaved forwardlyextending flange carried at the bottom of said front plate of said rear frame and an arcuate lower edge on said rear plate of said front frame, said lower edge having a radius of curvature equal to that of said flange and resting on the upper surface thereof, the center of the radius of curvature of said flange and said lower edge being coaxial with said longitudinal axis, a plurality of stub axles extending inwardly fromthe concaveupper side of said flange and a roller carried by each stub axle rotatably engaging the frontface ofthe rear plate of said from frame to hold said rear plate against said front plate.

, References. Cited in the file of this patent UNITED STATES PATENTS Germany Feb. 24,. 1933 

